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Finding the Fourth Proportional to 28.90, 39.87 and 17.25

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Solution

The fourth proportional to 28.90, 39.87 and 17.25 is: 23.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.90 : 39.87 = 17.25 : x
  2. Step 2: Convert to fraction form
    28.90/39.87 = 17.25/x
  3. Step 3: Cross multiply
    28.90x = 39.87 × 17.25
  4. Step 4: Simplify right side
    28.90x = 687.60
  5. Step 5: Solve for x
    x = 687.60/28.90
  6. Step 6: Final answer
    x = 23.79

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.